Senior Data Scientist

1 Month ago • 4 Years + • Data Analysis

Job Summary

Job Description

Welltech is seeking a Senior Data Engineer to join its Machine Learning team. The role involves designing and deploying impactful machine learning solutions for critical business functions such as LTV prediction, user classification, personalization, and content tagging. The engineer will analyze product and marketing performance, develop models for unstructured data (NLP, computer vision), and contribute to recommendation systems. Responsibilities include building internal tools, monitoring model performance, and collaborating with data engineers on pipelines. The role requires strong Python and SQL skills, experience with ML libraries, statistics, experimental design, and end-to-end ML pipelines, along with AWS services like SageMaker. Familiarity with MLOps, collaboration, and user behavior analysis is also expected.
Must have:
  • 4+ years of experience in Data Science or product analytics with ML
  • Proficient in Python and SQL
  • Experience with core DS/ML libraries (NumPy, Pandas, Scikit-learn, XGBoost)
  • Solid understanding of statistics and experimental design
  • Experience developing and evaluating ML models for business problems
  • Practical experience building end-to-end ML pipelines
  • Hands-on experience with AWS services (SageMaker, Glue, Redshift, Lambda)
  • Familiarity with MLOps practices
  • Strong collaboration skills
Good to have:
  • Experience with recommendation systems or personalization
  • Background in Marketing Science (MMM, attribution models, ROI estimation, uplift modeling)
  • Applied experience in NLP or computer vision
  • Familiarity with reinforcement learning or contextual bandits
  • Experience with Docker, Airflow, and Terraform
  • Interest in model interpretability and explainability
Perks:
  • Culture that champions personal and professional growth
  • Empowerment to inspire and make an impact
  • Focus on achieving meaningful outcomes and making a difference
  • Opportunity to be part of a movement creating a healthier world

Job Details

🚀 Who Are We?

Welcome to Welltech—where health meets innovation! 🌍 As a global leader in Health & Fitness industry, we’ve crossed over 220 million installs with three life-changing apps, all designed to boost well-being for millions. Our mission? To improve the health of millions of people through intuitive nutrition trackers, powerful fitness solutions, and personalized wellness journeys—all powered by a diverse team of over 750+ passionate professionals with a presence across 5 hubs.

Why Welltech? Imagine joining a team where your impact on global health and wellness is felt daily. At Welltech, we strive to be proactive wellness partners for our users while continually evolving ourselves.

What We're Looking For

We are looking for an experienced Senior Data Engineer to join the core Machine Learning team within a product-focused company. Our mission is to design and deploy impactful machine learning solutions that enhance decision-making and automate key business processes. We work closely with stakeholders across the company and take ownership of end-to-end ML systems — from raw data to deployed models and monitoring.

Key Responsibilities:

  • Design and deploy ML models that support critical business functions such as LTV prediction, user classification, personalization, and content tagging.

  • Analyze product and marketing performance using statistical and ML techniques to support data-driven decision-making.

  • Develop models for processing unstructured data: user reviews, feedback, support tickets (NLP), and creative assets (computer vision).

  • Contribute to the design and evolution of content recommendation systems and personalization logic.

  • Build internal tools and dashboards to increase model transparency and accessibility for business teams.

  • Monitor model performance and support the full model lifecycle: retraining, error analysis, version control.

  • Collaborate with data engineers to validate new features, contribute to pipeline standardization, and support data readiness for production use.

  • Provide analytical support to marketing teams: metric design, experiment planning, evaluation, and modeling impact.

Required Skills:

  • 4+ years of experience in Data Science or product analytics involving machine learning.

  • Strong proficiency in Python and SQL; hands-on experience with core DS/ML libraries such as NumPy, Pandas, Scikit-learn, and XGBoost.

  • Solid understanding of statistics, experimental design (A/B testing, uplift modeling), and causal inference.

  • Proven experience developing, evaluating, and interpreting ML models for real business problems — including classification, regression, recommendation systems, NLP, and computer vision.

  • Practical experience building and maintaining end-to-end ML pipelines: data preparation, feature engineering, training, validation, deployment, and monitoring.

  • Hands-on experience with AWS services, especially SageMaker, Glue, Redshift, and Lambda.

  • Familiarity with MLOps practices: model versioning, CI/CD, automated retraining, and monitoring.

  • Strong collaboration skills and the ability to work closely with product managers, analysts, and engineers.

  • Experience analyzing user behavior, running segmentation, and evaluating marketing or product experiments.

Nice to Have:

  • Experience with recommendation systems or personalization.

  • Background in Marketing Science: media mix modeling (MMM), attribution models, ROI estimation, uplift modeling.

  • Applied experience in NLP or computer vision (e.g., content classification, creative decomposition).

  • Familiarity with reinforcement learning or contextual bandits for optimization and personalization.

  • Experience with Docker, Airflow, and Terraform.

  • Interest in model interpretability and explainability tooling.

Tech Stack:

Python, SQL, DBT, AWS (SageMaker, Glue, Lambda, Redshift, Spectrum), Docker, Airflow, GitLab, Terraform, Flask, Streamlit.

Candidate journey: ⭕️ Recruiter call ➔ ⭕️ Meet the hiring manager ➔ ⭕️ Meet the leadership team


✨ Why You’ll Love Being Part of Welltech:

  • Grow Together: Join a culture that champions both personal and professional growth. Here, you’ll thrive as we learn, evolve, and succeed together.

  • Lead by Example: No matter your role, your leadership matters. Every team member is empowered to inspire and make an impact.

  • Results-Driven: We’re all about achieving meaningful outcomes. It’s not just about the effort, but the difference we make every day.

  • We Are Well-Makers: Be part of a movement that’s creating a healthier, happier world. Together, we make well-being a reality!


Check out some of our products

Muscle Booster — https://musclebooster.fitness/

Yoga-Go — https://yoga-go.io/

WalkFit -http://walkfit.pro

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About The Company

Welcome toWelltech—where health meets innovation! 🌍 As a global leader inHealth & Fitness industry, we’ve crossed over220 million installswith life-changing apps, all designed to boost well-being for millions. Our mission? To improve the health of millions of people through intuitive nutrition trackers, powerful fitness solutions, and personalized wellness journeys—all powered by a diverse team of over700+ passionate professionals with a presence across 5 hubs.Why Welltech?Imagine joining a team where your impact on global health and wellness is felt daily. At Welltech, we strive to be proactive wellness partners for our users, while continually evolving ourselves.

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